Study of the Salem-Attur shear zone, east of Salem, Tamil Nadu: a new kinematic interpretation

Abstract

A study of the mylonites of the Salem-Attur shear zone at Udayapatti and Sarkar Nattar Mangalam reveals that the shear zone developed in the form of a northeasterly vergent subhorizontal thrust which has been refolded into variable attitude due to late stage folding. The subhorizontal mylonitic foliation with NE trending stretching lineation bears testimony to such an explanation. The earlier impression that the shear zone is vertical comes from the folded part of the thrust as the mylonites have assumed a vertical attitude on the limb of the fold